Boston Computer Society - Sinclair Timex User Group Newsletter

BOO The Boston Computer Society
SINCLAIR-TIMEX USER GROUP NEWSLETTER

Volume 2, Issue 5 May 1983

This newsletter is produced to inform group members of the agenda and
logistics for future meetings, as well as to recap and amplify the information
provided at the last meeting. It also provides a forum for members and
interested parties to communicate what they have learned or developed relating
to Sinclair and Timex computer products. Meetings are open to the public;
however, attendees are encouraged to join the Boston Computer Society (BCS).
This newsletter is free to members. Back issues are one dollar each.

USER GROUP MEETING

Date: Wednesday, May 18, 1983
7:00 p.m.

Large Science Auditoriun
UMass, Harber Campus
(Directions on last page)

At the May meeting, Dan Roy will unveil the add-on color capability for
the T/S-1000. The product he developed is called COLORSIN81. It features a
high-resolution color display, sound, joy stick interface, and an expansion
capability via a 6-slot motherboard. Display features include three modes of
high-resolution color and a text mode with 24 lines, 40 characters per line.
There are powerful new commands, such as DATA, READ, RESTORE, block moves, and
plotting subroutines. All this for only $159.95 as a kit. In addition, Dan
will demonstrate the CAI/EXATRON stringy floppy mass storage device. Dan says
that the stringy floppy was essential for the development of COLORSINB1. With
the stringy floppy, one can load a 16 K program in about 15 seconds. Numerous
features, such as the capability to chain programs, are included in this
system.

Following Dan’s presentations, we will break into groups to discuss
topics of interest. Tentatively, an advanced and a beginner’s group are
planned.

At the June meeting, Dave Miller will demostrate and explain QSAVE and
FASTLOAD--programs which are available from Gladstone. If you have items to

discuss at a future meeting or suggestions for presentations, contact Sue or
Cliff.

WHAT“S DIFFERENT ABOUT THIS NEWSLETTER?

Dont worry, we“1ll tell you. This issue contains advertising.
Advertising helps offset the cost of publication and debuts product
information which may be of interest. We have established a few basic rules
to help guide us in this area. Anyone who is interested in these guidelines
or has suggestions contact Jack Hodgson, Publisher.

HIGHLIGHTS OF THE APRIL MEETING

As with the past several meetings, the April meeting was jam-packed with
activity--demonstrations, hardware and software discussions, and hints.

Sue Mahoney began the meeting with a demonstration of "Ator the ABC
Gator." Ator is a Timex program which synchronizes a fanciful display of the
letters of the alphabet with a song recorded on the cassette tape containing
the program, Simple procedures for synchronizing the computer and tape are
included in the program. When synchronized, the computer flashes letters on
the screen as the author sings her song. Ator is designed to teach the ABCs
to preschoolers. It*s interesting to note in passing that Ator, as other ABC
songs, contains that long letter in the center of the alphabet with which many
kids have trouble, namely LMNOP.

Following Sue”s presentation, Dave Wood demonstrated the new printer he
purchased and interfaced with his computer, the Okidata Microline 92. He
described his initial interfacing difficulties and how these were resolved
{contact Dave to save yourself these problems). He also described some of the
software he developed to use with the printer. See Dave“s article on page 4.

Gene Bachman showed some pictures of spectra and waveforms taken from
several tape recorders which illustrated differences between different
vecorders. See Gene“s article below.

Al Spencer reviewed the Parrot by R.I.S.T. Computer Components, Inc.,
P.O. Box 499, Fort Hamilton Station, NY 11209. The Parrot is a voice
synthesis module which plugs into the edge connector of our computer. When
the computer commands, the Parrot speaks in allophones. You must supply a
speaker. By using the proper sequence of allophones, speech is generated. Al
played a tape with several sentences spoken by the Parrot-~all were
understandable. The Parrot costs $89.95 plus $4 shipping and handling.

Also at the meeting, a number of shorter {tems were covered. Mike
Coughlin suggested a new way to avotd RAM pack wobble. His solution involves
installing an HM6264 8 by 64 K memory chip in the computer. Sue distributed
the first Issue of Ramblings, the Timex Computer Club newsletter. Sue also
awarded Cliff Danielson and John Kemeny Timex T-shirts for their efforts on
the newsletter. Will Stackman suggested the use of a Radio Shack 75 ohm
auto~duplication coaxial cable for replacing the cable between the computer
and the television.

A COMPARISON OF THREE RECORDERS by Gene Bachman

I began having loading probleme after I dropped my Radio Shack recorder
down the stairs. While it was in for repairs, I switched to a 10 year old,
$19 Montgomery-Ward portable. The Montgomery-Ward wouldn“t load at all until
I installed a 10 ohm resistor across the earphone jack. I also noticed a loud
background hiss when listening to a program. Timex” instructions say the
computer needs 4 volts peak-to-peak from the recorder. I measured the output
of the recorder with a digital voltmeter at less than one volt. This was
because the voltmeter measures an average, not peak-to-peak, voltage. When
the damaged Radio Shack recorder was returned, it was very unreliable. It had
a hiss, which it did not have before, and the speed wavered. At this point, I
decided to see just what made a recorder good or bad.

I played the same program (Psion flight simulator) on my two recorders
and on a Sony instrumentation recorder into a frequency spectrum analyzer. I
have access to a laboratory with such equipment. The three spectra computed

THREE RECORDERS (Continued)

from 256 samples of each signal, were so similar that no conclusions could be
drawn (see frequency spectrum figure). Since I couldnt make much sense of
the voltmeter readings or spectra, I finally resorted to the old reliable
oscilloscope, in this case, a Tektronix storage scope.

With the Sony recorder and a laboratory-grade decade amplifier, I
generated a 4 volt peak-to-peak signal. The computer liked this. It loaded
every program, every time. Looking at the signal on the oscilloscope, I could
see short and long tone bursts obviously representing zeros and ones.
Increasing the horizontal scale to 1 millisecond (ms) per division allowed me
to count the number of cycles in the bursts and to measure the frequency of
the tone. Four cycles of a 3.33 kHz tone represented a zero; nine cycles a
one. The total time to transmit a zero, that is, the length of the tone burst
plus dead time between two bursts, was 2.5 ms. This is a signaling rate of
400 baud, that is, 400 zeros can be transmitted in one second. The ones
occupied 4.0 ms for a signaling rate of 250 baud. I was not able to discern
the beginning or end of a byte; spaces between bits and bytes looked {dentical.

Now that I knew what the signal should look like, 1 played the program on
the old cheap recorder and on the damaged one. The differences were obvious
(see figures). Whereas the Sony signal was clean and symmetrical, the
Montgomery-Ward was distorted and unsymmetrical. The Radio Shack signal was
even more distorted, due, I suspect, to a bent drive shaft and misaligned
heads.

From my experience, I conclude that if a recorder set at 3/4 of full
volume has a lot of hiss when playing a new, unrecorded tape or has a wavering
or tinny sound when playing music, it will send the computer a distorted
signal. This makes it unreliable, even when loading tapes that were saved to
the same recorder. On my way home from the laboratory, I bought a new
Panasonic model RQ2735 and have had no more problems.

SONY RECORDER

OLD RECORDER

Ai

+r

DAMAGED RECORDER

INTERFACING A REAL PRINTER TO THE TIMEX/SINCLAIR 1000 by Dave Wood

This article describes how I
attached an Okidata Microline 92
dot-matrix printer to my MicroAce
computer. (The MicroAce is a copy of
the ZX-80 computer which I have modified
to be equivalent to the T/S 1000.) I
purchased the Okidata printer because of
its versatility and print fidelity. For
the money ($500-$600), one can get very
good type quality, almost like an impact
printer. The Okidata can print at 10,
12, and 17 characters per inch. It can
also print double width characters with
each pitch. It will accept up to 64
user-defined characters. This could be
used to generate most of the Sinclair Double Width Characters
characters. The printer can also print

individual dots for graphics output. Example of Print Quality

This Is Enhanced Printing.

This Is Emphasized Printing.

Electrical/Logical Interface with the Printer

The printer comes equipped with a “standard” Centronics-compatible
parallel interface. Exactly what Centronics-compatible means is not
immediately obvious. As I finally figured out, there are three important
elements in this interface. First, 8-bit characters are passed to the printer
on eight parallel data lines (one bit per wire). Second, an input strobe line
notifies the printer when the data (the 8-bit character) is ready on the
parallel data input lines. The strobe line is normally held at logical one
(+5 volts). When the data is ready, the signal on the strobe line should go
to logical zero (0 volts) for a microsecond or so and then return to a logical
one. The data is actually accepted by the printer on the rising edge of this
strobe pulse, i.e., when the signal level goes back to one. The third element
is a busy output line which notifies the computer that the printer doesn“t
want to get any new data. The second and third items constitute the handshake

protocol by which the computer and the printer agree on sharing the character
data.

My computer is equipped with the CAI/O Board interface from CAI
Instruments, Midland, Minnesota, which has, among other things, three 8-bit
parallel input/output ports. This interface can be configured (programmed) to
operate in different modes. The interface is memory mapped, so that
programming it or writing to an output port is accomplished by POKEing to
specific addresses and reading an input is accomplished by PEEKing. The
automatic parallel interface mode of the CAI/O interface, which has built-in
handshaking, was an obvious choice to use for the printer interface. Wrong!
It is not Centronics compatible. Thus, I had to use the CAI/O interface as a
simple (dumb) interface, providing the proper handshake protocol by software
in my computer.

I configured the three ports on the CAI/O interface as 12 bits out (8
bits of port A for data and 4 bits of port C for control) and 12 bits in (8
bits of port B for printer signals and the other 4 bits of port C unused).
The actual wiring of the cable between the Centronics-compatible connector at
the printer and the dual-15 edge connector on the CAI/O interface creates the
mapping of bits between the computer and the printer. Most of these bit
assignments, with the exception of the port A data lines, were arbitrarily
chosen.

This is an example of the qua

ABCDEFGHI JKLMNOPORSTUVWXY Zabcdef
HSITO P< arose, OL’ L121 ~&_IN%

This is printed at 17 characters per inch, which pernit:

It is alsa possible to printsuPerscrift

Software Interface with the Printer

At first I implemented the software interface in BASIC. But the program
vas uncomfortably slow. So I wrote the program in machine language. The
machine language program occupied only 242 bytes, including the ASCII
conversion table. To pass a character to the machine language program, 1 used
a fixed memory location. In this straight-forward approach, you POKE from
BASIC and read from the location in the machine language program. I used the
fixed address 16506 in the system variables area. My machine language
program, which handles the ASCII conversion and handshake protocol is located
at 32525. Thus, sending a character to the printer consists of:

POKE 16506, (character code) followed by RAND USR 32525.

Conceptually, translation from Sinclair character codes to ASCII can be
handled as a table look up. In other words, one could place in RAM a table of
256 ASCII characters which correspond to the 256 Sinclair characters, then
simply use the Sinclair character code to index into the table. However, a
bit more thought is required. Some judgment must be used, for example, to
decide how to map to the ASCII characters !, “, #, @, and others. There are
only 128 ASCII characters defined; also only 128 of the Sinclair characters
are printable. My conversion program allows me to treat either normal or
inverse vedio alphabet as the lower case ASCII characters.

The Centronics handshake protocol is simple to implement, as the program
below demonstrates. An important part of this code is use of ROM routines to
test for and act upon the break key. Testing for the break key allows one to
escape from the machine code and not be trapped in “never-never land” should
the printer hang up-

Enter with ASCII character in A reg. . ESCAPE FROM STALAG LUFT Il

DELAY UNTIL PRINTER READY
Set HL with input port(B) address.
PRINT LD HL,3COlh
Test to see if printer is busy.
TSTB BIT 0,(HL)

JR Z,OK
Save the character in A register.
PUSH AF rs to ores com inen knoe ee
Check for break key.
CALL OF46h
If break, exit to "D" return code.
JP NC,O03A6h
Recall the char.& see if still busy.
POP AF ae BALANCER
JR TSTB

OUTPUT CHARACTER AND STROBE
Change HL to output port(A) address.
OK DEC HL

Output the character.
LD (HL),A

Change HL to port C address.
INC HL
INC HL . Our cataiog, with screen display
RES 7,(HL)
SET 7,(HL) SIMULUSION, BOX 894, LEMON GROVE, CA 92045
RET

THE TIMEX/SINCLAIR AS AN INTELLIGENT LAB STATION TERMINAL by Larry Becker

Imagine a science laboratory
with up to 16 stations, each
containing a computer capable of
instrument control as well as analog
and digital data collection. Each
lab station computer could either
display the data as they are being
received or store the data. The
stored data could then be sent to a
larger computer for storage on disk
and later analysis and display. The
incoming data at the lab station
could be sampled at selectable time
intervals or, alternatively, sampled
at the request of an external signal.
In addition, the lab station could
generate digital or analog signals
for control of stepper motors or
voltage-controlled instrumentation used in experiments. A nice thought, you
say ... but, oh, the expense!

Now suppose that each lab station costs no more than $300 (including the
computer, computer memory, interfacing hardware, and CRT monitor); and the
large host computer with which the lab station communicates was an unmodified
Apple computer. Interested?

During the past few months at Technical Education Research Centers
(TERC), while on sabbatical leave from the Physics Department of Hiram
College, I have been developing the hardware and software which will turn the
Timex/Sinclair microcomputer into the intelligent lab station described above.
The T/S 1000 with 16 K memory pack can be purchased for under $100. A small
black and white television costs less than $100. The interface hardware which
allows the above capabilities has been built and thoroughly tested. And an
initial software capability has been developed. The hardware and
user-friendly software should not cost more than $100. A $300 lab station is
feasible. —

a! The prototype interfacing board (see figure 1) measures 7-1/2 by 5-1/2

inches. It should be possible to reduce the size to about 4 by 5 inches.
Consequently, not only will the cost be
low, but also the size will be such as to
take up very little space at the lab
station. The television monitor will be
the biggest part of the system.

Preliminary software includes four
programs. The first program displays the
voltage levels on two of the eight analog
input channels of the interface board (see
figure 2). A marker on the voltage line
for each channel moves back and forth as
the level is changed. A program such as
this would be helpful during experiment
set-up to determine if the voltage levels
from the equipment are within the 0 to 5
volt range needed for the interface
eircuitry.

INTELLIGENT LAB STATION (Continued)

The second program samples the input voltages and plots the values on a time
axis while the voltage is varying. For example, it generates a sine curve on
the monitor as a potentiometer is rotated by a swinging pendulum. In its
present form, the program plots the curve with 32 large squares. Double this
resolution is possible. A curve made up of 64 data points, however, is still
much too coarse for most experiments. Therefore, this program would be used
in setting up the experiment, not in collecting the actual data.

A third program allows the collection of 500 data points at sampling time
intervals of multiples of 100 microseconds. Once the data have been stored in
the Timex/Sinclair, the communications portion of the program, together with a
receive/send program in the Apple, can transfer the 500 data points to the
Apple in one half of one second. The transfer rate is 20,000 bits per second.
The connection to the Apple {s through the paddle port. Consequently, the
transfer of data can be made to an
Apple II, and Apple II+, and an Apple
Tle with no hardware modification.
Once the data have been transferred
to the Apple, a high resolution
graphics program can be run to plot
the data. Figure 3 shows the display
which was obtained after a 10 second
collection period (500 data points)
for a swinging pendulum.

A fourth program has been
written which allows the
Timex/Sinclair to receive data from 2 4 ‘ r
the Apple, again at 20,000 baud. In
the planning stage is software which Press return fen irerelvs, seme
will load programs from the Apple
into the Timex/Sinclair. With this
capability, a cassette tape recorder will not be needed at each station. When
all is completed, the system with up to 16 lab stations networked to the
Apple, will be controlled by the Apple. Each Timex/Sinclair will have the
capability to request programs from the Apple. The programs will include
those for specific experiments (e.g., the swinging pendulum) and general-use
programs.

Since the software is still in the development stage, I would appreciate
suggestions concerning types of programs you would find useful in your labs
(or any other environments you envision for the low cost networking system).
I left TERC to return to Hiram College at the end of March. However, I am
continuing work on the project. I hope that general user-friendly software
can become a reality by the end of the summer. Anyone interested in making
suggestions or receiving additional details of the project may call (216)
569-5248 or write: Larry Becker, Department of Physics, P.O. Box 1778, Hiram
College, Hiram, OH 44234.

DID YOU KNOW OR CARE?

The first two characters appearing together in the ZX-81 and TS-1000 ROM
are Zand X. These happen to be the first two characters of the keyboard
decode table which starts at location 126.

SINCLAIR STUDY GROUP

As you may be aware, there are a large number of Sinclair-Timex user
groups around the U.S. and Canada. We have tried to get in contact with them
by sending them our newsletter. Many have reciprocated. Recently, we asked
if we could reprint some of their material. The overall response was “great.”

This month we spotlight the Sinclair Study _Group, 16 Lewis Street, New
Haven, CT 06513. The group produces a terrific monthly newsletter, yearly
subscriptions to which are only $6. SUE MAHONEY IS COMING!! This was the
banner headline of the March issue. Below is Sues report of her visit.
Opposite are three edited (for space) excerpts from the SSG newsletter.

A Children*s User Group by Sue Mahoney

The New Haven Sinclair Study Group is a unique user group in that the

members ages range from 8 to 14 years old.

Chris Baldwin, the adult leader,

founded the group last year. Chris is a teacher in one of the alternative
schools in Hew Haven. The study group, although it has females, is
predominately male. It is a very enthusiast and energetic group. Each member

has a preject — some quite elaborate.

One of the group’s first projects was

to build the Sinclair 2X-81 kit. The youngest participant was only seven.

On my recent visit I demonstrated the T/S 2000. The group’s response was

overwhelming enthusium and excitement.

They were literally glued to the edges

of their seats. They asked many, many questions. I look forward to meeting
with them again. Chris indicated that anyone interested in starting a
children’s group or becoming a children’s group sponsor should contact him.

IT’S HERE!!
The keyboard you have
been waiting for!

A LARGE 60 KEY TACTILE. FEEL KEYBOARD
{MEASURES 10” x 4”) THAT PLUGS INTO THE SAME
CONNECTORS AS EXISTING KEYBOARD ON YOUR
ZX81 OR TIMEX SINCLAIR 1000. IT HAS ALL
SILKSCREENED LEGENDS IN 3 COLORS ON THE
BASE; MOLDED LEGENDS & GRAPHICS ON KEY TOPS,
8 AUTOMATIC SHIFT KEYS (NO SHIFTING REQUIRED)
FOR EDIT, DELETE, SINGLE & DOUBLE QUOTES,
COLON, SEMI-COLON, FUNCTION & STOP; 5" SPACE
BAR; 2 SHIFT KEYS; NUMERIC KEY PAD.

ONLY $84.95

MASS. RESIDENTS ADO 5% SALES TAX
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SENO SASE. SEND INQUIRIES, CHECK OR MONEY

ORDERTO: £.7 KEY
SUITE 75
711 SOUTHERN ARTERY
QUINCY,MA 02169

Dear Fellow Computerists,

I offer Timex software for people who want
to learn as well as just use. Every product
comes complete with instructions, program

listing, and a thorough enlightening text of

how the program works.

My programs are top quality too. In fact,
my ZX Data Finder program was reviewed
in SYNC. Here's what they said:

"ZX DATA FINDER is the best most
economical data handling program yet."
SYNC Magazine 1/83

They don't give reviews like that for junk.
Write for my free catalog. It has programs
for both BASIC and M.C. programmers.

Plus: PROWRITER PRINTERS for $399.95!!
Make your Volkswagen drive a Cadillac!

Thomas B. Woods
P.O. Box 64, Jefferson, NH 03583
Phone: (603) 586-7734

Chicken?

This 1 K game attempts to answer the age old question, “why did the
chicken cross the road?“ Guide the chicken (C) across the road to its home
(H) using the 8-key. Youll soon discover there are many vehicles (V) on the
road and there is no turning back.

How does the Sinclair know when the chicken is hit or gets home? Line 25
directs the computer to be ready to print the chicken at its new location.
But before the chicken is printed in line 45, the computer “looks” to see what
is already on the screen at the location. Line 30 PEEKs at addresses 16398
and 16399 to find the address of the next PRINT position of the display file.
Line 35 then PEEKs there to see if a V (character 59) is displayed. Line 40
does the same for H (character 45).

LET D=D+1
20 PRINT AT 0,31;"H" Poem by Matthew Quinlan
25 PRINT AT 0,C;
30 LET N=PEEK 16398+256*PEEK 16399 The ZX81 is compact and easy Co use.
35 IF PEEK N=59 THEN GOTO 90 It can do anything but tie your shoes.
40 IF PEEK N=45 THEN GOTO 10 Small and easy to lose.

45 PRINT “C” No zapping to give you the blues.
50 LET U$=STRS$ RND

Take you on paths yet unexplored.
You can play it at home and not get bored.
You don“t even need a 80 column board.

Plan your diet and not get fat.

75 IF INKEY$ ="8" THEN LET C=C+1 Like learning BASIC is where it is at.
80 SCROLL Learning BASIC is really hip.
85 GOTO 20 I mean gag me with a microchip!

90 PRINT “SPLAT ";30*(D-3)+C

Antique Flag - How Old Is It? by Kent Zimmermann

The program contains 13 lines but here is a way you can enter it by
typing in only four lines! Enter line 1. Now EDIT line 1: DELETE the line
number and replace it with a 10. Pretty tricky all right. &£DIT line 10 this
time, DELETE the line number and replace it with 30. Youve got the idea.
Enter and EDIT lines 5, 50, and 60 to finish the program. RUN up the flag and
feel good about being so clever.

1 PRINT “*#****8*XXXXXXXXXXKK"
5 PRINT "xkeRRRRE

10 PRINT “*#®*#*&*#KXXXXXXXKKKXX”

20 PRINT “****eeKR™ Line 1 contains 8 *"s and

30 PRINT “*##*k**kkXXXXXXXXXXKX” 20 graphics spaces

40 PRINT “*#exARRR™ Line 5 contains 8 *"s

50 PRINT “XXXXXXXXXXXXXXXXXXXX" Line 50 contains 20 graphics
60 PRINT Spaces

70 PRINT “XXXXXXXXXXXXXXXXXXKK"

80 PRINT

90 PRINT “XXXXXXXXXXXXXXXXXXXX"

100 PRINT

110 PRINT “XXXXXXXXXXXXXXXXXKXX"

TIMEX 1000

How will you take your ake
SYNTAX / Syntax Quarterly?

Budgetane scsesace eee $995

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The Combination—12 issues SYNTAX, 4 | Bookkeeping ss. sses++ 14.95
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Tel: (212) 486-0980

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PROG!

ROM BUG #3

There is an error in the ROM program in our computer which causes numbers
between 0.91 and 0.00001 to be LPRINTed incorrectly. The bug occurs only with
printers using the LPRINT command, such as the Timex and Sinclair printers.
Unlike the bugs we described in the December and January newsletters, this bug
could have a direct affect on you. Thanks goes to Gary Preston, editor of the
Franklin County User Group newsletter, Glade Hill, Virginia for first making
us aware of the problem. Gary says that anybody who has purchased the
Sinclair printer should know about the bug because it is mentioned in the
printer manual. Dave Miller discovered the additional information required to
complete this article.

Numbers, in magnitude (absolute value) less than one and containing two,
three, or four zeros following the decimal point, are LPRINTed incorrectly.
Below is what we got with the new Timex 2040 printer:

The first column is the correct output;

the second is created by LPRINT B and

LPRINT STRS$ B; the third by LPRINT AT 0,15; STRS$ B; the fourth by

LPRINT .001, etc. Numbers 0.01 or larger are printed correctiy. Numbers
smaller than 0.00001 are printed correctly, but in scientific notation. To
eliminate the problem replace the LPRINT statement with two statements, such
as LET BS=STR$ B and LPRINT BS. Note that two separate statements are
required, LPRINT STR$ B will not work correctly.

DISCOUNT ON NEW MAGAZINE: Timex Sinclair User is a 4-color, monthly,
people-oriented magazine and will hit the North American market with 100,000
issues in May. It is a North American version of Sinclair User, which has
been successful in Europe. The first issue features an exclusive interview
with Dan Ross, Chief Operating Officer (V-P.) of the Timex Computer
Corporation. Also, it contains an article, with photos, by Sue Mahoney about
how to start a user group. It costs $2.95 or $29.95 for 12 issues. The
publisher, J. Gladstone, has offered a $5 discount to user groups, which we
are passing on to members. Gladstone requires a minimum order and time is
limited, Contact us soon if you are interested. And, oh yes, your $24.95

subscription also gets you a free "$15 value”

arcade game cassette.

EDUCATOR’S NEWSLETTER: The TEC News is a quarterly newsletter to be published
by the Timex-Sinclair Fducator’s User Group at Texas Wesleyan College in
cooperation with the Timex Computer Corporation. It is free to educators.
The first edition, which is scheduled to be out in late April, will Feature
“Computer Literacy for a School Faculty for $1900.00" and an introduction to

BASIC for elementary school teachers.

M. Mark Wasicsko, Associate

Dean, School of Education, Texas Wesleyan College, Ft. Worth, TX 76105.

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SERIOUS PROGRAMMERS

*"MUST-HAVE” UTILITIES
For ZX-81 and T/S 1000 Computers

A oeistgepnerea~eene enene ee
FILE*SYS $10

Read/Write Cassette Data Tape Files
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FILE*BASIC $15

Save/Merge/Erase BASIC Segments
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FILE*VARS $5
Save/Restore Strings & Arrays
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BASIC*OLAY $10
Overlay/Copy BASIC Segments
{permits full use of 64K RAM)

Simple user interface via USR function
Well-documented eser manuals

Available on tape cassette tn relocatable wachine lang

SASE for info Check or MO delivers now

Sie Ware

6 Turning Mill Road
Lexington, MA 02173

FOR MORE INFORMATION

Sue Mahoney, Director of the Sinclair-Timex User Group
c/o The Boston Computer Society or call (203) 573-5816.

Jack Hodgson, Publisher
P.O. Box 526, Cambridge, MA 02238, (617) 354-7899

Cliff Danielson, Editor
14 Davis Road, Chelmsford, MA 01824, (617) 256~4638.

John Kemeny, Contributing Editor & User Group Correspondent
284 Great Road, Apt. D5, Acton, MA 01720.

Library Committee: Beth Elloitt, Sean O’Rahilly, and Bob Sanchez.

ADVERTISING INFORMATION
Computer Related Products and Services Only
Open Rate: $40 per Quarter Page
For Rate Card and Discount Information Contact the Publisher

DIRECTIONS TO THE MEETING

The Sinclair-Timex User Group meets in the Large Science Auditorium (Room
8/2/009) of the University of Massachussets of Boston, Harbor Campus. The
Harbor Campus is only 3 miles from downtown Boston and easily accessible by
public and private transportation. From the north or west, take the Southeast
Expressway to Exit 17. Turn left onto Columbia Road. Enter the rotary and
take the first right (Morrissey Boulevard). Bear right on the traffic island,
following UMass/Boston sign. Turn left into the Campus. From the south, take
Morrissey Boulevard northward to the campus. On the MBTA, take the Red Line
(Ashmont Train) to Columbia Station. Transfer to the free University
shuttlebus in the T parking lot.

QO Trice Boston,
OSComputer Society
Three Center Plaza

Boston, MA 02108
617-367-8080